Mrs. Jackson gives the table to her students. x y 4 26 5 23 6 a In order for the function to be linear, what must a be and why?

For a linear function, the rate of change must stay constant. From x = 4 to x = 5, y changes from 26 to 23, a decrease of 3. So when x increases from 5 to 6, y must decrease by 3 again, making a = 23 − 3 = 20. The correct choice is that a is 20 because the rate of change is negative 3.

AI-written and checked against the verified answer.